This invention relates to engines, pumps and other mechanism of similar nature, and in particular to such a mechanism having a crank shaft.
Various engines/pumps utilizing a crank shaft are currently known. Such engine/pumps are more commonly known as wobble engines/pumps or swash plate engines/pumps. Wobble engines/pumps have axial pistons disposed from a wobble plate which is fixed on an output/input shaft at an acute angle. In the case of an engine, power received from the pistons is transferred to the wobble plate during the power stroke, displacing the wobble plate axially, and as a result rotating the shaft. The operation of a wobble pump is in reverse order, wherein power is applied to the input shaft to displace fluid inside the cylinders.
Modern developments in wobble engines/pumps have included changes in the configuration and operation of the pistons/cylinders and in inlet/outlet porting of the fluids. The drive mechanisms of such modem machines are nevertheless very complex, requiring many parts which are both difficult to assemble and also difficult to maintain. Such engines/pumps also have a lot of components operating under high frictional forces.
Previously published New Zealand Patent No. 221366 discloses therein a means to transfer the wobbling motion of a disc to a rotary motion of the shaft and visa versa. Further disclosed therein is a suitable means of providing power to or from the disc by way of internal cylinder engine or hydraulic/pneumatic motors. There is however no detail on any means by which the cylinder engine is or can be coupled to either the disc or the shaft, such that the invention can operate as a compact simple unit.
New Zealand Patent No. 150235 describes a continuous disc acting as pistons inside a chamber. The disc is non planar and rotation thereof inside the chamber forms pockets which are compressed and expanded at differing angles of rotation.
The complex nature of the disc, output and crank shafts, chamber and other dependent mechanisms make such an engine/pump expensive and difficult to make.
New Zealand Patent No. 131852 describes a two stroke or four stroke engine also operable as a pump, in which pistons of circular cross-section which are bent in an arc are located inside curved cylinders disposed axially about a central axis. Power from the rotating cylinders is transferred to the output engine block, the spider in this invention remaining stationary.
Most modem wobble type engines/pumps require many complicated parts to ensure efficient operation. Difficulties exist in the sealing of cylinders to ensure that no fluid escapes undesirably, and in the assembly and maintenance. Such engines also have problems operating in balance.
It is an object of the present invention to provide an engine/pump which will at least provide the public with a useful choice.
Accordingly the present invention may broadly be said to consist in an internal combustion engine having
a crank shaft having a shaft axis and having a crank axis oblique to the shaft axis but aligned to intersect therewith at X,
an array of piston and xe2x80x9ccylinderxe2x80x9d assemblies to rotate as assemblies relative to and about said shaft axis, each said assembly having a reciprocal axis between its top dead centre (enforceable) (TDC) and bottom dead centre (BDC), each such reciprocal axis midway between TDC and BDC being normal to a line projected from X, each said xe2x80x9ccylinderxe2x80x9d being of any appropriate cross section (with respect to its reciprocal axis) and the cross section of each complementary piston being complementary to the cross section of its cylinder,
piston control means mounted to rotate about said crank axis,
connection means for each piston from said control means, the connection between each said connection means and said piston control means and/or between each said connection means and its piston having sufficient degrees of freedom to allow the requisite reciprocal movement of said pistons within each associated cylinder thereof as the array of assemblies rotates relative to and about the shaft axis,
cylinder head means which holds and/or defines the cylinders in said array, said head means including at least one port per cylinder, and
port means relative to which said cylinder head means moves sealably to allow (timed to the reciprocal movement of each piston in its cylinder and to the rotational position of each cylinder) the induction compression, power and exhaust strokes of a four stroke combustion engine
AND WHEREIN
at least one said connection means is capable of conveying torque between said crank shaft and said cylinder head means via its said piston and cylinder and via said piston control means, AND
means is provided whereby, directly or indirectly (eg; via said crank shaft), power can be taken off said cylinder head means or crank shaft or port means as each rotates relative to the other.
Preferably each said connection connects said piston control means to a pair of piston and cylinder assemblies, each piston and cylinder assembly of such a pair having a different head means (each of which in turn has its own said port means), and each said piston and cylinder assembly of such a pair having its said line projected from X at the same angle on either side of a line projected normal from the crank shaft axis at X.
Preferably said crank shaft is indexed, directly or indirectly, with said at least one cylinder head means.
Preferably said indexing is by annular and planetary gearing.
Preferably the power take off is from said crankshaft and said gearing transmits the geared torque as well as serving a timing function.
Preferably said port means, in sequence, can present an induction port or ports, optionally a spark plug and optionally a fuel injector, and an exhaust port or ports, the presentations being timed for a cylinder to the induction stroke, compression/power stroke and/or transition thereof, and exhaust stroke respectively.
Preferably the annular gear is carried by the cylinder head means, said planetary gears providing the indexing of said crank with said cylinder head means and having their rotatable axes fixed relative to said port means.
Preferably the ratio of crank shaft rotation to piston and cylinder assemblies rotation is 3:1 in a counter-rotating direction.
Preferably there are three pairs of opposed pistons and cylinder assemblies, the associated port means for each providing two inlet and two outlet ports.
Preferably said engine operates as or as if a diesel engine.
Preferably said engine operates as or as if a petrol engine
In another aspect the invention consists in an internal combustion engine having
a crank shaft having a shaft axis and having a crank axis oblique to the shaft axis but aligned to intersect therewith at X,
an array of piston and xe2x80x9ccylinderxe2x80x9d assemblies to rotate as assemblies relative to and about said shaft axis, each said assembly having a reciprocal axis between its top dead centre (TDC) and bottom dead centre (BDC), each such reciprocal axis midway between TDC and BDC being normal to a line projected from X, each said xe2x80x9ccylinderxe2x80x9d being of any appropriate cross section (with respect to its reciprocal axis) and the cross section of each complementary piston being complementary to the cross section of its cylinder,
piston control means mounted to rotate about said crank axis,
connection means for each piston from said piston control means, the connection between each said connection means and said piston control means and/or between each said connection means and its piston having sufficient degrees of freedom to allow the requisite reciprocal movement of said pistons within each associated cylinder thereof as the array of assemblies rotates relative to and about the shaft axis,
cylinder head means which holds and/or defines the cylinders in said array, and port means relative to which said cylinder head means moves sealably to allow (in conjunction with any other port(s), if any )(timed to the reciprocal movement of each piston in its cylinder and to the rotational position of each cylinder) at least the inflow of air and fuel and the power and compression of a two stroke combustion engine
WHEREIN
each combustion chamber as defined by each said piston, its cylinder and the cylinder head means can be timed for the exposure as required to two ports,
AND WHEREIN
at least one said connection means is capable of conveying torque between said crank shaft and said cylinder head means via its said piston and cylinder and via said piston control means, AND
means is provided whereby, directly or indirectly (eg; via said crank shaft), power can be taken off said cylinder head means or crank shaft or port means as each rotate relative to each other.
Preferably said head means includes at least two ports per cylinder.
Preferably each said connection connects said piston control means to a pair of piston and cylinder assemblies, each piston and cylinder assembly of such a pair having a different head means (each of which in turn has its own said port means), and each said piston and cylinder assembly of such a pair having its said line projected from X the same angle on either side of a line projected normal from the crank shaft axis at X.
Preferably said crank shaft is indexed, directly or indirectly, with said at least one cylinder head means.
Preferably said indexing is by annular and planetary gearing.
Preferably the power take off is from said crankshaft and said gearing transmits the geared torque as well as serving a timing function.
Preferably said port means, in sequence, can present an induction port or ports, optionally a spark plug, and optionally a fuel injector, the presentations being timed for a cylinder to the compression/power stroke and/or transition thereof, respectively wherein exhaust and induction occurs as substantially BDC of each piston.
Preferably the annular gear is carried by the cylinder head means, said planetary gears providing the indexing of said crank with said cylinder head means and having their rotatable axes fixed relative to said port means.
Preferably the ratio of crank shaft rotation to piston and cylinder assemblies rotation is 3:1 in a counter-rotating direction.
In yet a further aspect the present invention consists in a positive displacement machine having
a crank shaft to rotate about the shaft axis or having a shaft axis and having a crank axis oblique to the shaft axis but aligned to intersect therewith at X,
an array of piston and xe2x80x9ccylinderxe2x80x9d assemblies to rotate as assemblies relatively about said shaft axis, each said assembly having a reciprocal axis between its top dead centre (TDC) and bottom dead centre (BDC), each such reciprocal axis midway between TDC and BDC being normal to a line projected from X, each said xe2x80x9ccylinderxe2x80x9d being of any appropriate cross section (with respect to its reciprocal axis) and the cross section of each complementary piston being complementary to the cross section of its cylinder,
piston control means mounted to rotate about said crank axis,
connection means for each piston from said piston control means, the connection between each said connection means and said piston control means and/or between each said connection means and its piston having sufficient degrees of freedom to allow said piston control means to cause the requisite reciprocal movement of said pistons within each associated cylinder thereof as the array of assemblies rotates relative to and about the shaft axis,
cylinder head means which holds and/or defines the cylinders in said array, said head means including at least one port per cylinder, and
port means relative to which said cylinder head means moves sealably to allow (timed to the reciprocal movement of each piston in its cylinder and to the rotational position of each cylinder) the induction and delivery strokes of each piston
AND WHEREIN
at least one said connection means is capable of conveying torque between said crank shaft and said cylinder head means via its said piston and cylinder and via said piston control means, AND
means is provided whereby, directly or indirectly (eg; via said crank shaft), power can be applied to said cylinder head means or port means or crank shaft.
Preferably each said connection connects said piston control means to a pair of piston and cylinder assemblies, each piston and cylinder assembly of such a pair having a different head means (each of which in turn has its own said port means), and each said piston and cylinder assembly of such a pair having its said line projected from X the same angle on either side of a line projected normal from the crank shaft axis at X.
Preferably said crank shaft is indexed, directly or indirectly, with said at least one cylinder head means.
Preferably said indexing is by annular and planetary gearing.
Preferably the power delivery is to said crankshaft and said gearing transmits the geared torque as well as serving a timing function.
Preferably said port means, in sequence, can present an induction port or ports, and delivery port or ports, the presentations being timed for a cylinder to the induction stroke, delivery/compression stroke and/or transition thereof.
Preferably the annular gear is carried by the cylinder head means, said planetary gears providing the indexing of said crank with said cylinder head means and having their rotatable axes fixed relative to said port means.
Preferably the ratio of crank shaft rotation to piston and cylinder assemblies rotation is 3:1 in a counter-rotating direction.
Preferably there are three pairs of opposed pistons, and cylinder assemblies, the port means for each providing two inlet and two outlet ports.
In still a further aspect the present invention consists in a combustion engine having
a crank shaft having a shaft axis and having a crank axis oblique to the shaft axis but aligned to intersect therewith at X,
an array of piston and xe2x80x9ccylinderxe2x80x9d assemblies to rotate as assemblies relative to and about said shaft axis, each said assembly having a reciprocal axis between its top dead centre (TDC) and bottom dead centre (BDC), each such reciprocal axis midway between TDC and BDC being normal to a line projected from X, each said xe2x80x9ccylinderxe2x80x9d being of any appropriate cross section (with respect to its reciprocal axis) and the cross section of each complementary piston being complementary to the cross section of its cylinder,
piston control means mounted to rotate about said crank axis,
connection means for each piston from said piston control means, the connection between each said connection means and said piston control means and/or between each said connection means and its piston having sufficient degrees of freedom to allow the requisite reciprocal movement of said pistons within each associated cylinder thereof as the array of assemblies rotates relative to and about the shaft axis,
cylinder head means which holds and/or defines the cylinders in said array, said head means including at least one heat transfer region per cylinder, and
heat exchange means relative to which said cylinder head means moves to allow (timed to the reciprocal movement of each piston in its cylinder and to the rotational position of each cylinder) the heat transfer to and from the working fluid in each said cylinder
AND WHEREIN
at least one said connection means is capable of conveying torque between said crank shaft and said cylinder head means via its said piston and cylinder and via said piston control means, AND
means is provided whereby, directly or indirectly (eg; via said crank shaft), power can be taken off said cylinder head means or crank shaft or port means as each rotates relative to each other.
Preferably each said connection connects said piston control means to a pair of piston and cylinder assemblies, each piston and cylinder assembly of such a pair having a different head means (each of which in turn has its own said port means), and each said piston and cylinder assembly of such a pair having its said line projected from X the same angle on either side of a line projected normal from the crank shaft axis at X.
Preferably said crank shaft is indexed, directly or indirectly, with said at least one cylinder head means.
Preferably said indexing is by annular and planetary gearing.
Preferably the power take off is from said crankshaft and said gearing transmits the geared torque as well as serving a timing function.
Preferably said port means, in sequence, can present an induction port or ports, optionally a spark plug and optionally a fuel injector, and an exhaust port or ports, the presentations being timed for a cylinder to the induction stroke, compression/power stroke and/or transition thereof, and exhaust stroke respectively.
Preferably the annular gear is carried by the cylinder head means, said planetary gears providing the indexing of said crank with said cylinder head means and having their rotatable axes fixed relative to said port means.
Preferably the ratio of crank shaft rotation to piston and cylinder assemblies rotation is 3:1 in a counter-rotating direction.
In still a further aspect the present invention consists in an internal combustion engine having
a crank shaft having a shaft axis and having a crank axis oblique to the shaft axis but aligned to intersect therewith at X,
an array of piston and xe2x80x9ccylinderxe2x80x9d assemblies to rotate as assemblies relative to and about said shaft axis, each said assembly having a reciprocal axis between its top dead centre (TDC) and bottom dead centre (BDC), each such reciprocal axis midway between TDC and BDC being normal to a line projected from X, each said xe2x80x9ccylinderxe2x80x9d being of any appropriate cross section (with respect to its reciprocal axis) and the cross section of each complementary piston being complementary to the cross section of its cylinder,
piston control means mounted to rotate about said crank axis,
connection means for each piston from said piston control means, the connection between each said connection means and said piston control means and/or between each said connection means and its piston having sufficient degrees of freedom to allow the requisite reciprocal movement of said pistons within each associated cylinder thereof as the array of assemblies rotates relative to and about the shaft axis,
cylinder head means which holds and/or defines the cylinders in said array, said head means including at least two ports per cylinder, and
at least one inlet and one outlet valve per cylinder each actuable directly or indirectly by the relative rotation of said crank shaft to allow (timed to the reciprocal movement of each piston in its cylinder and to the rotational position of the cam) the induction compression, power and exhaust strokes of a four stroke combustion engine
AND WHEREIN
means is provided whereby, directly or indirectly (eg; via said crank shaft), power can be taken off said crank shaft as it rotates relative to said cylinder head means.
Preferably each said connection connects said piston control means to a pair of piston and cylinder assemblies, each piston and cylinder assembly of such a pair having a different head means (each of which in turn has its own said port means), and each said piston and cylinder assembly of such a pair having its said line projected from X the same angle on either side of a line projected normal from the crank shaft axis at X.
Preferably a cam is rotatable about said crank axis to control the motion of each valve.
Preferably said cam is indexed, directly or indirectly, to said crank shaft.
Preferably said indexing is by annular and planetary gearing.
Preferably the power take off is from said crankshaft and said gearing transmits the gearing increased torque to the cam to serve as a timing function.
Preferably the annular gear is carried by the cylinder head means, said planetary gears able to orbit about said shaft axis and providing the indexing of said cam with said cylinder means and having their rotatable axes fixed relative to said cam.
Preferably said engine operates as a diesel engine.
Preferably said engine operates as or as if a petrol engine.
In yet another aspect the present invention consists in an internal combustion engine having
a crank shaft having a shaft axis and having a crank axis oblique to the shaft axis but aligned to intersect therewith at X,
an array of piston and xe2x80x9ccylinderxe2x80x9d assemblies to rotate as assemblies relative to and about said shaft axis, each said assembly having a reciprocal axis between its top dead centre (TDC) and bottom dead centre (BDC), each such reciprocal axis midway between TDC and BDC being normal to a line projected from X, each said xe2x80x9ccylinderxe2x80x9d being of any appropriate cross section (with respect to its reciprocal axis) and the cross section of each complementary piston being complementary to the cross section of its cylinder,
piston control means mounted to rotate about said crank axis,
connection means for each piston from said piston control means, the connection between each said connection means and said piston control means and/or between each said connection means and its piston having sufficient degrees of freedom to allow the requisite reciprocal movement of said pistons within each associated cylinder thereof as the array of assemblies rotates relative to and about the shaft axis,
cylinder head means which holds and/or defines the cylinders in said array, said head means including at least two ports per cylinder, and at least one inlet valve per cylinder actuable directly or indirectly with the relative rotation of said crank shaft to allow (timed to the reciprocal movement of each piston in its cylinder and to the rotational position of the cam) the induction of air into its corresponding cylinder and compression, power strokes of a two stroke combustion engine
AND WHEREIN
means is provided whereby, directly or indirectly (eg; via said crank shaft), power can be taken off said crank shaft as it rotates relative to said cylinder head means.
Preferably said head providing means includes at least two ports per cylinder.
Preferably each said connection connects said piston control means to a pair of piston and cylinder assemblies, each piston and cylinder assembly of such a pair having a different head providing means (each of which in turn has its own said port means), and each said piston and cylinder assembly of such a pair having its said line projected from X the same angle on either side of a line projected normal from the crank shaft axis at X.
Preferably a cam is rotatable about said crank axis to control the motion of each valve.
Preferably said cam is indexed, directly or indirectly, with said each cylinder head means.
Preferably said indexing is by annular and planetary gearing.
Preferably the power take off is from said crankshaft and said gearing transmits the gearing increased torque to the cam to serve as a timing function.
Preferably the annular gear is carried by the cylinder head means, said planetary gears able to orbit about said shaft axis and providing the indexing of said cam with said cylinder head means and having their rotatable axes fixed relative to said cam.
In still a further aspect the present invention consists in an internal combustion engine having as at least part of an assembly,
a shaft carrying a precessing crank,
at least one combustion chamber each indexed at some rate to the relative rotation of said shaft yet port for two or four stroke cycle operation,
at least one piston or other compression/driven type complementary member for said combustion chamber (hereinafter xe2x80x9cpistonxe2x80x9d) to orbit said precessing crank, each for a combustion chamber,
a connection member to move each piston in its combustion chamber as required for said two or four stroke cycle operation, and
a member or members (hereinafter xe2x80x9cwobbling member(s)xe2x80x9d)mounted as if journalled directly or indirectly from said precessing crank (or equivalently thereto) and controlling the piston moving motion of each connection member as the assembly rotates,
the power strokes of each piston via its said connection member, said wobble member(s), said crank and the indexing driving or driving from said output shaft.
In still a further aspect the present invention consists in an internal combustion engine comprising
at least one shaft carrying a precessing crank, the crank axis intersecting obliquely the shaft axis or aligned shaft axes of said at least one shaft,
at least one combustion chamber to orbit relative to said shaft axis of said at least one shaft at an indexed rate or a port member (hereinafter referred to), said combustion chamber(s) having at least one passageway to allow flow of fluids into and out of said combustion chamber,
at least one compression member such as a piston (hereinafter xe2x80x9cpistonxe2x80x9d) to orbit relatively said crank axis and to act as the compression and/or driven member (eg. piston) of said combustion chamber(s),
at least one member (hereinafter xe2x80x9cwobbling memberxe2x80x9d) mounted as if journalled directly or indirectly to said precessing crank so as to be able to rotate relative to and about said crank axis to thus wobble about the shaft(s) axis and controlling the motion of said piston(s), and
at least one port or multiple port member (hereinafter xe2x80x9cport memberxe2x80x9d) over which said at least one opening rotates to provide at known intervals,
(i) at least one opening for fluid to flow in to and/or out of each combustion chamber(s), and
(ii) a closure to each said combustion chamber(s).
Preferably said precessing crank is carried between two precessing crank carrying members each forming part of or secured to opposed (in direction) output shafts positioned on a common axis, the central axis of precession of said precessing crank being coaxial with said axis of rotation of said output shafts, the intersection of said crank axis and said axis of rotation of said output shafts being between said precessing crank carrying members.
Preferably the axis of said wobbling member(s) extends through said intersection such that motion induced by said wobbling member(s) on said pistons is rotational only.
Preferably connection rods extend from the distal end of said wobbling member(s) to said at least one piston, said piston capable of rotating and translating relative to said wobbling member(s) to maintain a motion coaxial with it respective said combustion chamber(s).
Preferably said combustion chamber(s) is located inside a combustion chamber housing, said combustion chamber housing coupled to said output shaft(s) by at least one coupling means such that rotation of said at least output shaft(s) induces proportional rotation of said combustion chamber housing (or vice versa) about said axis of rotation of said output shaft(s) in the same or opposite rotational direction.
Preferably a plurality of wobbling members extend from said precessing crank. Each axis of said wobbling members extend through said intersection. Each wobbling member carries two connection rods extending in opposite directions. Said connection rods are journalled directly or indirectly to its respective said wobbling member, and are able to rotate relative thereto and able to translate along said wobbling member axis relative thereto.
Preferably said wobbling member has disposed therefrom and positioned on a plane normal to said crank axis and passing through said intersection, at least one piston substantially in the form of a segment of a disc, the circumferential edge of said at least one piston (during operation of said engine), tracing part of an imaginary sphere,
said combustion chamber(s) defined at least by,
(i) an outer casing defined by said imaginary sphere,
(ii) said at least one port or multiple port member,
(iii) radially extending walls, located adjacent the radial edges of said at least one piston, and
(iv) said wobbling member.
Preferably said wobbling member is spherical in shape in at least that part defining said combustion chamber(s).
In still a further aspect the present invention consists in a fluid displacement/compression machine having as at least part of an assembly,
an input shaft carrying a precessing crank,
at least one compression chamber indexed at some rate to the rotation of said input shaft yet port for fluid displacement/compression,
at least one piston or other compression/driven type complimentary member for said compression chamber (hereinafter xe2x80x9cpistonxe2x80x9d) to orbit said precessing crank, each for a compression chamber,
a connection member to move each piston in its compression chamber as required for said fluid displacement/compression, and
a wobbling member or members mounted as if journalled directly or indirectly from said precessing crank (or equivalently thereto) and controlling the piston moving motion of each connection member as the assembly rotates,
the displacement/compression strokes of each piston via its said connection member, said wobble members and crank pin driven by said output shaft.
In yet a further aspect the present invention consists in a fluid displacement/compression machine comprising
at least one input shaft carrying a precessing crank, the crank axis intersecting at an incline to the axis of rotation of said at least one input shaft,
at least one compression chamber to orbit said axis of rotation of said at least one input shaft at a some rate relative to said input shaft(s) or said port member (hereinafter referred to) said compression chamber(s) having at least one passageway to allow flow of fluids in to and out of said compression chamber,
at least one compression/displacement member such as a piston (hereinafter xe2x80x9cpistonxe2x80x9d) to orbit said crank axis and to act as the compression and/or driven member (eg. piston) of said compression chamber(s),
at least one wobbling member mounted as if journalled directly or indirectly to said precessing crank so as to be able to rotate relative to said crank axis to wobble about the rotational axis of said input shaft(s) and controlling the motion of said piston(s), and
at least one port or multiple port member (hereinafter xe2x80x9cport memberxe2x80x9d) over which said at least one opening rotates to provide at known intervals,
(i) at least one opening for fluid to flow in to and/or out of each compression chamber(s), and
(ii) a closure to each said compression chamber(s).
Preferably said precessing crank is carried between two precessing crank carrying members each forming part of or secured to opposed (in direction) input shafts positioned on a common axis, the central axis of precession of said precessing crank being co axial with said axis of rotation of said input shafts, the intersection of said crank axis and said axis of rotation of said input shafts being between said precessing crank carrying members.
Preferably the axis of said wobbling member(s) extends through said intersection such that motion induced by said wobbling member(s) on said pistons is rotational only.
Preferably connection rods extend from the distal end of said wobbling member(s) to said at least one piston, said piston capable of rotating and translating relative to said wobbling member(s) to maintain a motion coaxial with it respective to said combustion chamber(s).
Preferably said compression chamber(s) is located inside a compression chamber housing, said compression chamber housing coupled to said input shaft(s) by at least one coupling means such that rotation of said at least input shaft(s) induces proportional rotation of said compression chamber housing (or vice versa) about said axis of rotation of said input shaft(s) in the same or opposite rotational direction.
Preferably a plurality of wobbling members extend from said precessing crank, each axis of said wobbling members extending through said intersection, each wobbling member carrying two connection rods extending in opposite directions, said connection rods journalled directly or indirectly to its respective said wobbling member, and able to rotate relative thereto and able to translate along said wobbling member axis relative thereto.
Preferably said wobbling member has disposed therefrom and positioned on a plane normal to said crank axis and passing through said intersection, at least one piston substantially in the form of a segment of a disc, the circumferential edge of said at least one piston (during operation of said engine), tracing part of an imaginary sphere,
said compression chamber(s) defined at least by,
(i) an outer casing defined by said imaginary sphere,
(ii) said at least one port or multiple port member,
(iii) radially extending walls, located adjacent the radial edges of said at least one piston, and
(iv) said wobbling member.
Preferably said wobbling member is spherical in shape in at least that part defining said compression chamber(s).